'.ipython/profile_ssh' not found

I'm trying to start cluster with ssh. The following error message appears in engine log:
```
2021-12-08 00:42:19.562 [IPEngine] Config changed: {'ProfileDir': {'location': '.ipython/profile_ssh'}, 'IPEngine': {'work_dir': '/home/xd/project/Finance/quant_v1', 'profile': 'ssh'}, 'Session': {'key': b'8dc49daa-41cace1936b400470864d3d2', 'signature_scheme': 'hmac-sha256', 'packer': 'json', 'unpacker': 'json'}, 'IPKernelApp': {'exec_lines': [], 'exec_files': []}, 'HistoryManager': {'hist_file': ':memory:'}}
2021-12-08 00:42:19.562 [IPEngine] CRITICAL | Profile directory '.ipython/profile_ssh' not found.
```
It looks like I should set absolute path for 'ProfileDir': {'location': '.ipython/profile_ssh'}, but I don't know how to do that.
I've tried setting ```c.ProfileDir.location = '/home/xd/.ipython/profile_ssh'``` in ipcluster_config.py with no luck...
Thanks.

Start with the SSH cluster configuration and the `ProfileDir.location` setting in `ipcluster_config.py`, then reproduce the startup command while checking the engine log. Trace how the relative profile path is resolved for the engine process. Done means the SSH-launched engine finds its profile directory and starts without the reported error.

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